New snow continues to pile up. Expect to see a natural avalanche cycle lasting through Monday.
Weather Forecast
Moist, mild Pacific air collides with a cold Arctic High. Forecasts predict anywhere from 40-140cm of snowfall by Monday evening. Alpine winds are mainly moderate SW. Temperatures will drop as the arctic air re-establishes itself Monday in to Tuesday, winds will remain light and variable at all but the upper elevations.
Snowpack Summary
Up to 80cms and counting (60-80cm more is forecast) with light-moderate wind, this overlies: wind-hardened snow exposed areas, near surface facets in sheltered areas, and a melt-freeze crust below 2000m on solar aspects. The lower snowpack facets remain as a persistent concern and have produced isolated Sudden results in snowpack tests.
Avalanche Summary
Nearby operations reported a widespread storm slab problem yesterday, which was easily triggered by skiers and explosives.
Confidence
Forecast snowfall amounts are uncertain
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.